Melissa M Gouge, Gregory Gipson, Chandramohan Kattamuri
et al.
The differential screening-selected gene in neuroblastoma (DAN) family of antagonists are secreted extracellular proteins which preferentially bind to and inhibit BMP ligands. SOSTDC1 (Sclerostin domain containing protein 1) is a divergent member of the DAN family which has previously been shown to perform dual roles as a BMP inhibitor and a Wnt modulator. With the current understanding of SOSTDC1, it is challenging to determine the effect of SOSTDC1 activity within the BMP-Wnt signaling gradients, which are commonly seen in development, gut homeostasis, and female reproduction. SOST, the closest homologue of SOSTDC1, is a monomeric inhibitor of WNT signaling, binding to LRP6 β-propeller domain 1 through a conserved motif (NXI) but does not inhibit BMPs. Our lab has previously shown that unlike SOST, SOSTDC1 exists as a stable non-disulfide linked dimer, which binds to and inhibits BMPs. In this study we aimed to characterize the dimer conformation of SOSTDC1, focusing on how differences between SOST and SOSTDC1, particularly the dimeric structure, are responsible for their differences in function. We determined an X-ray crystal structure of a truncated SOSTDC1 dimer at 2.1Å resolution. The crystal structure, which was also validated by SAXS, revealed a divergent dimer interface when compared to other DAN family members. This conformation allows the NXI motif to be solvent exposed, leaving two NXI motifs free for LRP6 binding. In vitro cell signaling assays showed that SOSTDC1 inhibits Wnt1 (LRP6 β- propeller domains 1-2) mediated signaling. Surprisingly, when tested against Wnt3a (LRP6 β-propeller domains 3-4), we found that treatment with SOSTDC1 promotes signaling. It is hypothesized that this may be due to a SOSTDC1 pre-formed LRP6 dimer complex on the cell surface. The determination of the SOSTDC1 crystal structure unveils a new dimerization motif among the DAN family and allows for a better understanding of the mechanism of action of SOSTDC1. A molecular understanding of SOSTDC1 will support characterization of the Wnt-BMP axis in development.
Angélica Miamoto, João Paulo Rodrigues Marques, Cláudia Regina Dias-Arieira
The genus Meloidogyne is one of the most significant groups of plant-parasitic nematodes. Plant species capable of inhibiting the development and reproduction of this pathogen can be utilized as a management strategy. This study aimed to analyze the structural (constitutive and induced) and biochemical defense responses of the legume Macrotyloma axillare 'Java' in interaction with Meloidogyne javanica. The response of 'Java' to M. javanica was evaluated in two trials by inoculating 2000 eggs and second-stage juveniles (J2), with tomato used as a susceptible control. The reproduction factor (RF) was assessed 60 days after inoculation (DAI). Histochemical tests were conducted to observe constitutive and induced defense traits in 'Java' and tomato at 10, 20, and 30 DAI. Additionally, the reaction with 3,3'-diaminobenzidine was evaluated at 5 DAI, and root tips were examined using scanning electron microscopy at 30 DAI. The total protein content in roots was also measured at 8 and 12 DAI. In both trials, 'Java' showed RF < 1 (0.7 and 0.8) and was considered resistant to M. javanica, while tomato was susceptible, with RF > 1 (16.7 and 21.2). Histochemical analyses revealed constitutive defenses in 'Java', including the accumulation of phenolic compounds in phloem ducts and widespread suberin thickening in endodermal cells, whereas tomato exhibited only limited suberin thickening. Induced defenses in 'Java' included nematode females surrounded by cells with phenolic compound and protein accumulation, as well as deformed females and malformed giant cells with few cell wall invaginations at feeding sites. In tomato, feeding site development and nematode reproduction occurred without the accumulation of defensive compounds. Reaction with 3,3'-diaminobenzidine was more pronounced in 'Java' (42%) compared to tomato (23%). Scanning electron microscopy showed that giant cells in 'Java' were, on average, 46% smaller than those in tomato. Furthermore, 'Java' exhibited higher total protein levels when inoculated with M. javanica compared to the non-inoculated plant or tomato. In conclusion, 'Java' exhibits both constitutive and induced defense traits, which inhibit the full development and reproduction of M. javanica in its roots.
Lauren G. Hitt, Malte Willmes, George Whitman
et al.
Abstract As fish populations face compounding pressures under climate change, highly modified rivers are receiving increasing research and conservation attention as important sites for restoration. Across the North Pacific Ocean, Chinook salmon (Oncorhynchus tshawytscha) have experienced unprecedented declines and extirpations because of habitat loss and fragmentation and climate variability. Here, we studied a rare example of a novel salmon population developing in Putah Creek, California, a dam‐controlled stream flowing through an area of intensive agriculture where salmon were unlikely to occur prior to the rehabilitation of a more natural flow regime. We used otoliths from adult Chinook salmon carcasses recovered from Putah Creek to determine river or hatchery of origin for five spawning year classes. Our results provide evidence of successful salmon reproduction, outmigration survival, and natal homing of individuals back to Putah Creek in recent years. Although hatchery‐origin fish that strayed to Putah Creek to spawn dominated returns each year, this study documents life‐cycle completion required for the potential development of a self‐sustaining salmon population. This study demonstrates that targeted restoration and flow rehabilitation efforts can generate viable new salmon spawning habitat in dam‐controlled river systems, which could help mitigate habitat lost to dams and developments. Further, successful anadromous life‐cycle completion can occur in new spawning habitat within the first several generations, which will help inform efforts to restore or reintroduce salmon in other altered river systems.
Objective The process of a stainless steel train body derailment accident in urban rail transit in 2015 is simulated, reproducing the direct cause and process of the car body damage in the complex accident scene. Method Based on the investigation of the accident scene and the stainless steel car body structure and characteristics, the finite element method is used to reconstruct the accident model and analyze the changes of the speed, acceleration and energy of the train. Result & Conclusion Simulation results show that the intermediate cars climbing, snaking and colliding with each other caused by huge energy and rugged ground at the time of the accident forms the main reason for the fracture failure of stainless steel car body structure in the accident. The car body fractures mainly locate at the connections between the cab frame and the under-frame, the end wall and the roof, the under-frame and the side wall, as well as the under-frame and the end wall.
Nicholas E. Korres, Jason K. Norsworthy, Toby FitzSimons
et al.
Abstract The evolution of secondary sex-specific traits of dioecious species under abiotic stress conditions has received limited research, especially in the case of Amaranthus palmeri, a fast adapting and highly competing plant. Here, we have examined the interactive effects of abiotic stress on mineral accumulation, chlorophyll a and b content, and the operating capacity of Photosystem II (PSII) in both male and female A. palmeri plants grown under three different intensities of white light, and under N, K or P deficiency. Mineral profiling of the leaves and stems (with inflorescence) highlighted intra- and intersexual differences in their accumulation pattern and mineral associations. Chlorophyll a and chlorophyll b were different between the male and the female plants, being slightly lower in the latter, at high light intensity towards maturity, or under K or P deficiency. Further, slight, although statistically significant differences were recorded in the chlorophyll a/b ratio, which was lower at the higher light intensity in the female, over that in the male, plants towards maturity. Chlorophyll fluorescence parameters, i.e., steady state and maximum fluorescence increased under high light intensity, whereas the PSII operating efficiency decreased in the female plants, indicating reduced PSII capacity. Sex-specific differences in A. palmeri showed a differential response to stressful conditions because of differences in their ontogeny and physiology, and possibly due to the cost of reproduction. We suggest that the breeding system of dioecious species has weaknesses that can be used for the ecological management of dioecious weeds without relying on the use of herbicides.
Owen T. Watson, Gabriele Buchmann, Paul Young
et al.
Abstract Background Polyandrous social insects such as the honey bee are prime candidates for parental manipulation of gene expression in offspring. Although there is good evidence for parent-of-origin effects in honey bees the epigenetic mechanisms that underlie these effects remain a mystery. Small RNA molecules such as miRNAs, piRNAs and siRNAs play important roles in transgenerational epigenetic inheritance and in the regulation of gene expression during development. Results Here we present the first characterisation of small RNAs present in honey bee reproductive tissues: ovaries, spermatheca, semen, fertilised and unfertilised eggs, and testes. We show that semen contains fewer piRNAs relative to eggs and ovaries, and that piRNAs and miRNAs which map antisense to genes involved in DNA regulation and developmental processes are differentially expressed between tissues. tRNA fragments are highly abundant in semen and have a similar profile to those seen in the semen of other animals. Intriguingly we also find abundant piRNAs that target the sex determination locus, suggesting that piRNAs may play a role in honey bee sex determination. Conclusions We conclude that small RNAs may play a fundamental role in honey bee gametogenesis and reproduction and provide a plausible mechanism for parent-of-origin effects on gene expression and reproductive physiology.
Desde mediados del siglo XX el campo científico de las ciencias sociales viene experimentando transformaciones en la trayectoria de su institucionalización, ya que la tendencia a la reducción del número de categorías disciplinarias que desde 1850 se venía identificando, fue invertida tras la Segunda Guerra Mundial mediante un constante incremento de nombres. Empero, dicha multiplicación no parece haber estado desarrollándose de manera proporcional a la necesaria comunicación que debiera haber entre ellas, sugiriendo tal fenómeno una propensión de las ciencias sociales modernas a la hiperespecialización de sus materias y, por ende, al incremento y expansión de los vacíos entre sus campos afines (también llamados aquí «espacios No man’s land»). Por ello, en razón de que dicha circunstancia parece estar constituyendo un bloqueo en la capacidad explicativa del campo y de que su estudio puede coadyuvar a su desobstrucción, se ha centrado la presente investigación en aportar una mirada micro y macro de la disciplina a través del abordaje de las distintas fases mediante las cuales esta se desarrolla, por un lado; y a partir de la identificación de los condicionamientos socioculturales a los que esta está expuesta, por otro. Del análisis de estas cuestiones se han obtenido dos aspectos que parecen caracterizar la producción del conocimiento en las ciencias sociales modernas, los cuales son: a) la existencia de un mayor riesgo de obstrucción en la construcción disciplinaria tras la fase de especialización —en razón de que es en dicho momento cuando la actividad investigativa tiende a ser más proclive a quedar atrapada en la hiperespecialización—, y b) la tendencia a una mayor valoración, por su aplicabilidad a los intereses sociales, de los atributos nomotéticos frente a los idiográficos —cuya reproducción en el conocimiento se produce a través de mecanismos de legitimación—; pudiendo extraerse de dichos resultados lo que parece ser una relación causal entre la tendencia nomotética de la actual hiperespecialización, el incremento de los vacíos idiográficos entre campos afines y la necesidad de legitimación de las teorías en el universo simbólico contemporáneo.
Since the mid-twentieth century, the scientific field of social sciences has been transforming the trajectory of its institutionalization. This is because the trend towards reducing the number of disciplinary categories that had been identified since 1850 was reversed after the Second World War through a steady increase in names. However, such multiplication does not seem to have been developed proportionally to the necessary communication that should exist between them; suggesting a propensity of modern social sciences to hyper-specialize its subjects and therefore, to increase and extend the gaps between their related fields (also called here “No man’s land” spaces). This circumstance seems to be constituting a blockage in the field’s explanatory capacity, and studying it can contribute to unblocking it. Thus, the present research has focused on providing a micro and macro view of the discipline, on the one hand describing different phases through which it is developed and, on the other hand, by identifying the sociocultural conditioning to which it is exposed. From the analysis of these questions, two aspects have been obtained that seem to characterize the production of knowledge in modern social sciences, which are: a.) the existence of a higher risk of obstruction in the disciplinary construction after the specialization phase- because it is when research activity tends to be more likely to be trapped in hyperspecialization-, and b.) the tendency towards a greater appreciation due to its applicability to social interests of nomothetic attributes as opposed to idiographic ones-whose reproduction in knowledge is produced through mechanisms of legitimization. From these results, we can extract what seems to be a causal relationship between the nomothetic tendency of the current hyperspecialization, the increase of idiographic gaps between related fields, and the need for the legitimization of the theories in the contemporary symbolic universe.
Introduction Transgender (trans) individuals have unique medical needs and difficulty accessing quality health care, exacerbated by inadequate provider knowledge. Incorporation of trans health care into medical school curricula has increased recently to address this gap. Jigsaw activities emphasize positive interdependence through structured cooperative learning, resulting in increased interest and self-confidence. We implemented a voluntary 2-hour modified jigsaw exercise on trans health care with changes designed to optimize the structure for medical students. Methods The session was implemented both in person and virtually over 2 years with preclerkship medical students at the end of their endocrine/reproduction physiology course. The session featured a knowledge test with answer discussion followed by a clinical correlation—either a case discussion or video discussion. A pre- and posttest design compared students’ knowledge, attitudes, and beliefs. Results Eighty-nine students participated. Their initial attitudes and beliefs regarding trans health care were highly positive and remained elevated. Participants showed increases in knowledge and self-confidence discussing gender identity and clinical care postsession. All expressed interest in further training and felt the session enhanced their understanding of trans health and reproductive physiology. On 1-year follow-up, students showed decreased knowledge and self-confidence in discussing trans health; however, scores remained higher than presession. Student surveys suggested formal integration of more trans health education into the curriculum. Discussion Medical students increased their knowledge and self-confidence regarding trans medicine and felt the modified jigsaw exercise was an effective teaching method. The results suggest that ongoing education is an important tool in optimizing trans health care.
Federica Barca, Stefano Dalle Palle, Luca Schiavon
et al.
Since 1996, the Adriatic sturgeon (<i>Acipenser naccarii</i>) has been inscribed on the IUCN Red List as “Critically Endangered and possibly extinct in the wild”. Nowadays, its survival totally depends on restocking programs conducted by releasing juveniles generated from adult breeders reared in aquaculture. Conducting accurate genetic characterizations of all individuals potentially involved in reproduction activities is therefore of primary importance to avoid inbreeding and to maximize the genetic diversity transmitted to following generations. Since all animals reared in captivity descend from a single stock of wild origin, this offers the ideal condition for carrying out relatedness analysis based on parentage allocations. In this study, we provided the most complete characterization of about 500 individuals representing the most diverse extant stock of Adriatic sturgeon. Through the analyses of mitochondrial d-loop and 15 microsatellite loci selected from 24 genotyped loci, we identified about 30 different familiar groups, updating data on breeding stocks, increasing the genetic information already available, and extending the analyses to animals never genotyped before. Given its completeness, it will represent a reference database for any future parental allocation of recaptured animals for the inclusion of all other stocks present, as well as for the development of a long-term breeding plan. The approach used has also been proven useful on individuals of unknown genealogy, allowing for the identification of family groups and thus being proven to be promising for the analysis of stocks of other tetraploid sturgeon species.
Caitlin E McDonough-Goldstein, Kirill Borziak, Scott Pitnick
et al.
AbstractSexual reproduction in internally fertilizing species requires complex coordination between female and male reproductive systems and among the diverse tissues of the female reproductive tract (FRT). Here, we report a comprehensive, tissue-specific investigation of Drosophila melanogaster
Dana Rubi Levy, Yizhak Sofer, Vlad Brumfeld
et al.
The vomeronasal organ (VNO) specializes in detection of chemosignals, mainly pheromones, which control social communication and reproduction in many mammals. These pheromones must solubilize with nasal fluids before entering the VNO, and it was suggested that they are delivered to and cleared from the VNO by active pumping. Yet, the details of this pheromone delivery process are unclear. In this study, we first constructed a high-resolution 3D morphological image of the whole adult mouse snout, by using ultra-high-resolution micro-CT. We identified a net of micro tunnels starting from the nostrils and extending around and through the VNO. These micro tunnels connect the nasal cavity with the VNO and the oral cavity via the nasopalatine ducts (NPD). Other micro tunnels connect the nasal cavity to the main olfactory epithelium. We next demonstrated that physical obstruction of the NPD severely impairs the clearance of dissolved compounds from the VNO lumen. Moreover, we found that mice with blocked NPD display alterations in chemosignaling-evoked neuronal activation in brain regions associated with the vomeronasal system. Finally, NPD-blocked male mice exhibit reduced preference for female chemosignals, and impaired social interaction behavior. Taken together, our findings indicate that the NPD in mice are connected to both the nasal and oral cavity, serving an essential role in regulating the flow of soluble chemosignals through the VNO, and are required for proper pheromone-mediated social communication.
The renewable energy based smart grid present a stable power supply system with low carbon emissions. The adaptability of work in smart grid-related approaches allows microgrids to load reliably. This research proposes a self-healing method with a large smart grid in different purpose. The proposed technologies include re-dispatch generation, reconfiguration organizations, and load restrictions. Smart network self-healing problems are defined as integer quadratic problems. This paper presents a flexible model solution to promote a horizontal generation. Innovation settings reliability of electrical reliability smart grid modification is used to instruct reproduction in various circumstances. The results of recreation show the ability of the proposed self-healing scheme because it reduces the cost of load outages and generation with ideal exchange activities. The proposed system demonstrates self-healing capabilities to ensure smart network security by constantly preventing fault and adaptation planning generations. Simulation results from the (Western Systems Coordinating Council) WSCC 3 generator system adjusted with the microgrid module confirm the power system of the proposed structure. Keywords: Smart grid, Self-healing, Microgrid, Reliability